[PATCH BlueZ v4 1/6] mgmt: Add Security Level Changed event

["Frédéric Danis" <frederic.danis@collabora.com>]

This provides a TLV list of values related to the security level of
the connection to a remote device.

Currently Security Level and Encryption type are implemented.
---
v1->v2: Fix struct mgmt_ev_security_level_changed definition
v2->v3: Re-work Security Level possible values in mgmt-protocol.rst to be in
        with other *-protocol.rst files
v3->v4: Following changes in kernel patch, replace tlv_count by tlv_length

 doc/mgmt-protocol.rst | 45 +++++++++++++++++++++++++++++++++++++++++++
 lib/bluetooth/mgmt.h  | 15 +++++++++++++++
 2 files changed, 60 insertions(+)

diff --git a/doc/mgmt-protocol.rst b/doc/mgmt-protocol.rst
index f0564075f..f4c6822bf 100644
--- a/doc/mgmt-protocol.rst
+++ b/doc/mgmt-protocol.rst
@@ -5521,3 +5521,48 @@ The Supervision_Timeout parameter specifies the supervision timeout in units
 of 10 ms.
 
 This event will be sent to all management sockets.
+
+Security Level Changed
+``````````````````````
+
+:Event Code:		0x0034
+:Controller Index:	<controller_id>
+:Event Parameters:	Address (6 Octets)
+:...:			Address_Type (1 Octet)
+:...:			TLV_Length (1 Octet)
+:...:			TLV_List (variable)
+
+This event indicates that the security level of a device has changed.
+
+Possible values for the TLV type parameter:
+
+.. csv-table::
+	:header: "Type", "Description"
+	:widths: auto
+
+	0x0000, Security Level
+	0x0001, Encryption type
+
+Possible values for the Security Level type:
+
+.. csv-table::
+	:header: "Value", "Security Level", "Link Key Type", "Encryption"
+	:widths: auto
+
+	**BT_SECURITY_SDP**, 0 (SDP Only), None, Not required
+	**BT_SECURITY_LOW**, 1 (Low), Unauthenticated, Not required
+	**BT_SECURITY_MEDIUM**, 2 (Medium - default), Unauthenticated, Desired
+	**BT_SECURITY_HIGH**, 3 (High), Authenticated, Required
+	**BT_SECURITY_FIPS** (since Linux 3.15), 4 (Secure Only), Authenticated (P-256 based Secure Simple Pairing and Secure Authentication), Required
+
+Possible values for the Encryption type:
+
+.. csv-table::
+	:header: "Value", "Description"
+	:widths: auto
+
+	0x00, No encryption
+	0x01, E0 encryption
+	0x02, AES-CCM encryption
+
+This event will be sent to all management sockets.
diff --git a/lib/bluetooth/mgmt.h b/lib/bluetooth/mgmt.h
index 098be2074..af71be828 100644
--- a/lib/bluetooth/mgmt.h
+++ b/lib/bluetooth/mgmt.h
@@ -1142,6 +1142,20 @@ struct mgmt_ev_conn_subrate {
 	uint16_t supv_timeout;
 } __packed;
 
+#define MGMT_CONN_SEC_ENCRYPT_NONE		0x00
+#define MGMT_CONN_SEC_ENCRYPT_E0		0x01
+#define MGMT_CONN_SEC_ENCRYPT_AES_CCM		0x02
+
+#define MGMT_SEC_LEVEL_CHANGED_PARAM_LEVEL	0x0000
+#define MGMT_SEC_LEVEL_CHANGED_PARAM_ENC_TYPE	0x0001
+
+#define MGMT_EV_SECURITY_LEVEL_CHANGED		0x0034
+struct mgmt_ev_security_level_changed {
+	struct mgmt_addr_info addr;
+	uint8_t	tlv_length;
+	uint8_t	tlv_data[];
+} __packed;
+
 static const char *mgmt_op[] = {
 	"<0x0000>",
 	"Read Version",
@@ -1291,6 +1305,7 @@ static const char *mgmt_ev[] = {
 	"Mesh Packet Found",
 	"Mesh Packet Complete",
 	"Connection Subrate",
+	"Security Level Changed",
 };
 
 static const char *mgmt_status[] = {
-- 
2.43.0